COTTON VARIETIES 



41 



importance of soil and climate as factors influencing the 

 variability of cotton. 



47. Classification of varieties. — It is very difficult to 

 classify cotton varieties owing to the readiness with which 

 they are cross-fertilized and the great range of variation 

 of the individual plants within a variety. The most 

 satisfactory classification, of Ameri- 

 can upland varieties known to the 

 author is that proposed by Duggar 

 of the Alabama Experiment Sta- 

 tion which is given belOw: 

 , Group 1. — Cluster type. 



Group 2. — Semi-cluster type. 



Group 3. — Rio Grande type, of 

 which the Peterkin is an example. 



Group 4. — The early varieties 

 of the King type. 



Group 5. — The Big-boll type. 



Group 6. — The Long-limbed 

 type. 



Group 7 

 ties. 



Group 8. 

 varieties. 



48. Cluster type (Fig. 8). — The 

 plants of this type possess the char- 

 acteristic property of producing one 

 or more long basal limbs with ex- 

 tremely short spur-like fruiting 

 limbs on the niiddle and upper 

 parts of the main-stems. There is a tendency for the 

 bolls and leaves to be borne in clusters as a result of 

 the shortening of the internodes of the primary and fruit- 



■ Intermediate varie- 



Long-staple Upland 



Fig. 8. — Plant of the 

 Jackson Limbless va- 

 riety of cotton repre- 

 senting the O luster 

 group. 



